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Thirty three aryl and aryl alkyl phosphane ligands were prepared and characterized for catalytic purposes. The aryl groups in both types of ligands were modified with alkyl substituents (methyl, ethyl, isopropyl, cyclohexyl, phenyl) or hetero substituents (methoxy, N,N-dimethylaniline, thiomethyl). The alkyl groups directly attached to the phosphorous atom were ethyl, isopropyl or cyclohexyl. Mono- and in some cases also dinuclear palladium (II) complexes of the ligands were prepared and characterized. The syntheses of the palladium complexes are solvent-dependent and afford either mono- or dinuclear complexes depending on the choice of the solvent. Additionally, two 2-mercaptobenzothiazole palladium complexes were synthesized and characterized. A rare distorted lantern-type structure was presented for the first time. The ligands were characterized by 1H, 13C, 31P NMR spectroscopy and mass spectrometry. The palladium complexes were characterized by 31P NMR spectroscopy, X-ray crystallography and elemental analysis. Links between the NMR data of the palladium complexes and ligands and their catalytic activity was screened and correlation found. The crystal structures of the palladium complexes were studied for possible attractive interactions between two ligands. Such interactions were found from two examples. There is an attractive interaction between the phenyl and quinolinyl moieties of 2-quinolinyldiphenyl phosphane. A similar interaction was found between the methyl substitute and phenyl ring of o-tolylphosphane. The ligands and palladium complexes presented in this thesis were prepared in hope of finding suitable catalysts for Suzuki coupling reactions of various bulky aryl halides and phenyl boronic acids to prepare sterically hindered bi- and triaryls under microwave irradiation. A selection of aryl alkyl phosphane ligands catalyzed the couplings of bulky aryl bromides and even unactivated aryl chlorides efficiently and produced high yields. The reaction conditions of a new catalyst system were optimized, and it was noticed that the addition of a small amount of water enhanced the purity and yield of the coupling products further.

Group 11 metal complexes of the mesocyclic thioether aminophosphonites [-OC10H6(mu-S)C10H6O-]PNC4H8E {2a: E = O; 2b: E = NMe; IUPAC names: 4-(dinaphtho[2,1-d:1',2'-g][1,3,6,2]dioxathiaphosphocin-4-yl)morpholine (2a), 1-(dinaphtho[2,1-d:1',2'-gl[1,3,6,2]dioxathiaphosphocin-4-yl)- 4-methylpiperazine (2b)} are reported. Thioether aminophosphonites 2a and 2b react with CuX (X = Cl, Br, and I) in a 1:1 molar ratio to give the tricoordinate, dimeric complexes [{[{-OC10H6(mu-S)C10H6O-}PNC4H8E-kappa P]Cu(mu-X)}(2)] (4a: E = O, X = Cl; 4b: E NMe, X = Cl; 5a: E = O, X = Br; 5b: E = NMe, X = Br; 6a: E = O, X = I; 6b: E = NMe, X = I), whereas with 2:1 molar ratios monomeric complexes of the type [{[-OC10H6(mu-S)C10H6O-]PNC4H8O-kappa P)(2)CUX] (7a: E = O, X = Cl; 7b: E = NMe, X = Cl; 8a: E = O, X = Br; 8b: E = NMe, X = Br; 9a: E = O, X = I; 9b: E = NMe, X = I) are obtained in excellent yield. The PS-chelated cationic complexes [{[-OC10H6(mu-S)C10H6O-]PNC4H8E-kappa P,kappa S](2)Cu]BF4 (10a: E = O; 10b: E = We) are obtained when 2a and 2b are treated with half an equivalent of [(MeCN)(4)Cu]BF4. Similarly, the silver complexes [{[{-OC10H6(mu-S)C10H6O-}PNC4H8E-kappa P,kappa S]-AgCF3SO3}(2)] (11a: E = O: 11b: E = NMe) and [{[-OC10H6(mu-S)C10H6O-]PNC4H8E-kappa P,kappa S)Ag(PPh3)]CF3SO3 (12a: E = O; 12b: E = NMe) are synthesized by the treatment of thioether aminophosphonites 2a and 2b with AgOTf and [Ag(PPh3)][OTf], respectively. Reactions of 2a and 2b with [AuCl(SMe2)] produce the simple monomeric gold(I) complexes [{[-OC10H6(mu-S)C10H6O-]PNC4H8E-kappa P)AuCl] (13a: E = O; 13b: E = NMe). The iodo derivatives [{[-OC10H6(mu-S)C10H6O-]PNC4H8E-kappa P)AuI] (14a: E = O; 14b: E = NMe) are obtained by the halide-exchange reaction of 13a and 13b with CuI at room temperature. The structures of complexes 5a, 7a, 8a, 13a, 13b, and 14a are confirmed by single-crystal X-ray diffraction studies. In all of these complexes, the sulfur atom in the mesocyclic ring shows coordinative interaction towards the phosphorus atom, and in 5a, 7a, 8a, and 14a towards the metal center as well.

Palladium(II) acetate complexes with diethyl 8-quinolylmethylphosphonate (8-dqmp) and monoethyl 2-quinolylmethylphosphonate (2-Hmqmp) were synthesized and evaluated for their cytotoxic and antiviral activity in vitro in different cell lines. Structure-activity relationship studies comprise acetate and chloro complexes of the phosphonate ligands. Cell growth inhibitory effects in micro molar range were observed for the dichloro adduct and acetate bridged dimer of 8-dqmp.

24 pages revue; This review deals with the chemistry of phosphinines. As many reviews are available on the syntheses of these derivatives, only the most versatile methods are presented, or the ones giving access to the phosphinines that have been particularly studied. Then, recent results obtained in the coordination chemistry of phosphinines are summarized with an emphasis on their analogy with CO ligands. Indeed, the first studies proved these ligands to be well adapted for the stabilization of electron rich metal centers. Shortly after, highly reduced complexes have been obtained through the reaction of reduced 2,2'-biphosphinine dianions with transition metal fragments. Theoretical calculations were performed to establish the oxidation state of the metal in these complexes. On the other hand, the various coordination studies have pointed out that phosphinines become sensitive toward nucleophiles once they are bound to (even slightly) oxidized metal centers. This sensitivity precluded their use in most catalytic processes, but the cases in which they could be used efficiently are presented in this review. Two ways to circumvent this drawback were developed lately. The first method relies on the use of the high electrophilicity of the phosphorus atom of the phosphinine moiety. The ring is readily transformed into phosphacyclohexadienyl anions, which exhibit surprising coordination chemistry and promising behavior in catalysis. Results in this domain are presented. The second method is based on the involvement of the ring, as phosphadiene, into [4+2] Diels Alder type cycloadditions leading to phosphabarrelene derivatives. These ligands also show promising results in catalytic processes. Finally, phosphinines have been used successfully to stabilize gold nanoparticles, which opens a whole new field of applications for these ligands.

The title complex has been synthesized by first reacting dppp with Pd(AcO)2 in acetone and then with NaHSO4 in water. It has been characterized by IR, NMR and X-ray diffraction studies. The 31P NMR spectrum in DMSO shows a singlet at 16.62 ppm indicating that the two P atoms are equivalent and that the sulfate anion is weakly coordinating. The X-ray structure shows that the Pd atom is surrounded in an almost regular square planar environment by the two P atoms and by two O atoms of the sulfate anion and that the neutral complex is accompanied by a water molecule of crystallization. The Pd–P distances (2.217(1) and 2.233(1)) and the P–Pd–P angle (90.78(3)°) are close to those found in other complexes where the chelating diphosphine is the same. Also the Pd–O distances and the O–Pd–O bond angle are comparable to those of other relevant chelating ligands. In MeOH, the title complex, in combination with H2SO4, catalyses the CO-ethene copolymerization. The productivity reaches a maximum upon increasing the H2SO4/Pd ratio up to ca. 470 (7650 g of polyketone/g Pd h at 90 °C and 45 atm, CO/ethene 1/1). The viscosity of the polyketone passes through a maximum of 0.95 dL/g in m-cresol when the above ratio is ca. 100. It has been proposed that acid promotes the copolymerization process by destabilizing the β- and γ-chelates intermediates involved in chain growing process, thus favoring the insertion of the monomers. At relatively high acid concentration the lowering of productivity and viscosity suggests that the sulfate anion competes with the monomers for the coordination to the metal center. In H2O–CH3COOH as a solvent the productivity strongly depends on the H2O/CH3COOH ratio, as it passes through a maximum of 12 000 g polymer/g Pd h in the presence of ca. 60% of H2O. The productivity is significantly lower than that found when the acetate and chloride analogues are used (27 000 g polyketone/g Pd · h). Thus, it is likely that the sulfate anion assists significantly the copolymerization process even though the concentration of CH3COOH/CH3COO− is much preponderant.

For the first time, palladium complexes with salicylaldehyde thiosemicarbazones were applied as catalyst precursors to the Suzuki-Miyaura reaction. These air and moisture stable phosphine-free systems efficiently catalyze the cross-coupling of aryl bromides and chlorides (from electron rich to electron poor) with phenylboronic acid in DMF/H2O at 100 degrees C for 24 h, using Na2CO3 as base, without addition of free ligand or any promoting additive, and under aerobic conditions no significant homocoupling of phenylboronic acid to unsubstituted biphenyl was observed. (C) 2005 Elsevier Ltd. All rights reserved. Tetrahedron Lett

Two unprecedented types of ligands, with comparable essential coordination features, are proposed as supports for metal centres in bimetallic promotion of organic syntheses, including asymmetric catalytic processes. Synthesis and characterization of the bis-chelating bipyridine ligands A with C2 symmetry and X-ray analysis of one bipyridine diimine palladium binuclear complex are described. Synthesis and X-ray analysis of the bis-phenylimino derivative of a dibenzodioxepine dialdehyde are also reported. This dialdehyde is a key intermediate in the attainment of bis-isoquinoline ligands B with the same symmetry as A.

6 pages; The addition of O2 on SPS-type pincer-based Rh(I) and Ir(I) complexes was studied by means of DFT calculations. The regioselectivity and the influence of the nature of the metal center on the reaction thermicity were related through a thermodynamic cycle to the electronic properties of the metal complex and to the energetics of the M-O bonds. The synthesis and the X-ray crystal structure analysis of the Ir(I) complex are also presented.

Dichalcogenene complexes of the formula [cation]n[M(dmit) 2]n-, [cation]n[M(dmt)2] n-, and [cation]n[M(tbs)2]n- [M = Ni, Cu, Pd, Pt; Au, n = 0-2; dmit = 4,5-dimercapto-1,3-dithiole-2-thione, dmt = 4,5-dimercapto-1,2-dithiole-3-thione and tbs = thiobenezeneselenolate, cation = trimethyltelluronium, (CH3)3Te+, bis(triphenylphosphine)iminium, PPN+, tetrabutylammonium, Bu 4N+, and trimethylammonium, Me3NH+] have been prepared. The spectroscopic and electrochemical behaviour have been studied and compared with the related complexes. Oxidation reactions of these complexes with iodine afforded partially oxidized derivatives which exhibit compressed electrical conductivites of > 10-6 S cm-1 at room temperature. The [PPN][Au(dmit)2] complex has been structurally characterized by X-ray crystallography and its structure is compared with the structure of previously reported complexes [(CH 3)3Te][Au(dmit)2] and [PPN][Ni(dmit) 2].

Two series of cationic palladium(II) complexes, [Pd(phen)(L) 2 ][PF 6 ] 2 (L=pyridine ( 1a ), 2-picoline (2-pic) ( 1b ), 3-picoline (3-pic) ( 1c ), 4-picoline (4-pic) ( 1d )) and [Pd(CH 3 )(L)(phen)][OTf] (L=2-pic ( 2b ), 3-pic ( 2c ) and 4-pic ( 2d )), with mono and bidentate nitrogen-donor ligands bound to the same metal center have been synthesized and characterized. For the dicationic derivatives the study of the chemical behavior in solution evidences the presence of restricted rotations around the PdN bond of the monodentate ligand, generating syn and anti isomers. Depending on the nature of L the rate of this dynamic process is different on the NMR time scale. On the other hand, only the syn isomer was found by the X-ray analysis in solid state of one of these complexes. The dicationic complexes have been tested as precatalysts in the CO/styrene copolymerization, in comparison with [Pd(phen) 2 ][PF 6 ] 2 . The main difference between the two kinds of precatalysts is related to the stability of the corresponding active species, being lower for the complexes [Pd(phen)(L) 2 ][PF 6 ] 2 than for the bischelated derivative. The insertion reaction of carbon monoxide in the Pdmethyl bond was studied on the monocationic complexes, [Pd(CH 3 )(L)(phen)][OTf]. In all cases the corresponding Pdacyl species [Pd(COCH 3 )(L)(phen)][OTf] was formed with no dissociation of the monodentate L ligand. No effect of the nature of L on the rate of the insertion reaction was evidenced.

Organochalcogenido-bridged dimeric 2-methylallylpalladium complexes of the type [Pd-2(mu-ER)(2)(eta(3)-C4H7)(2)] (1) [ER = SBut (1a), SPh (1b), SC6F5 (1c), SePh (1d), TePh (1e)] have been prepared. The structure of the SBut bridged complex has been established by single crystal X-ray diffraction analysis. The four-membered Pd2S2 ring adopts a non-planar conformation with the two eta(3)-2-MeC3H4 (eta(3)-C4H7) in a syn configuration. The thermal behaviour of these complexes has been investigated by thermogravimetric analysis. These complexes yield Pd4E (E = S or Se) or Pd3Te2 at moderately low temperatures.

Complexes of types [Pd(CH3COO)(na)])xH2O, Hna=adenine (Hade) or guanosine (Hguo), x=2 � or 3; [Pd(CH3COO)2 (0.5 Hado)]2H2O, Hado=adenosine; [Pd(NH3)(na)(aa)3H2O, Hna=Hguo or inosine (Hino), Haa=glycine or alanine and [Pd(NH3)(gly)(0.5 ade)]2NO3H2O have been synthesised and characterized by elemental and thermal analyses, electronic, infrared, 1H NMR spectral and XPS studies. In acetato complexes, adeninate and guanosinate act as bridging ligand through the ring nitrogens N3 or N1 and N9, and N1 and N7 respectively giving polymeric structure while adenosine bridges the Pd(II) centers through N1 and N7. In amino acidato complexes, nucleosides coordinate through N1 to Pd(II) and adeninate bridges the two adjacent Pd(II) through N1 or N3 and N9.

The outcome for patients with advanced metastatic and recurrent prostate cancer is still poor. Therefore, new chemotherapeutics are required, especially for killing cancer stem cells that are thought to be responsible for disease recurrence. In this study, we screened the effect of a novel palladium-based anticancer agent (Pd complex) against six different prostate cancer cell lines, and primary cultures from seven Gleason 6/7 prostate cancer, three Gleason 8/9 prostate cancer and four benign prostate hyperplasia patient samples, as well as cancer stem cells selected from primary cultures. MTT and ATP viability assays were used to assess cell growth and flow cytometry to assess cell cycle status. In addition, immunofluorescence was used to detect gamma H2AX nuclear foci, indicative of DNA damage, and Western blotting to assess the induction of apoptosis and autophagy. The Pd complex showed a powerful growth-inhibitory effect against both cell lines and primary cultures. More importantly, it successfully reduced the viability of cancer stem cells as first reported in this study. The Pd complex induced DNA damage and differentially induced evidence of cell death, as well as autophagy. In conclusion, this novel agent may be promising for use against the bulk of the tumour cell population as well as the prostate cancer stem cells, which are thought to be responsible for the resistance of metastatic prostate cancer to chemotherapy. This study also indicates that the combined use of the Pd complex with an autophagy modulator may be a more promising approach to treat prostate cancer. In addition, the differential effects observed between cell lines and primary cells emphasise the importance of the model used to test novel drugs including its genetic background, and indeed the necessity of using cells cultured from patient samples. YÖK Yorkshire Cancer Research Core Grant UK Research & Innovation (UKRI) Medical Research Council UK (MRC) European Commission (G0900871) UK Research & Innovation (UKRI) Medical Research Council UK (MRC) (G0900871)

A new series of palladium(II) complexes of general formula [Pd(dppp)(L–L)][PF6]2 has been synthesised and characterised [dppp = Ph2P(CH2)3PPh2, L–L = 2,2′-bipyridine (bipy), 4,4′-dimethyl-2,2′-bipyridine, phenanthroline or 3,4,7,8-tetramethyl-1,10-phenanthroline]. The crystal structure of [Pd(dppp)(bipy)][PF6]2 has been determined. The chemical behaviour of the complexes in solution has been studied by NMR spectroscopy. Depending on the nature of the solvent, the chemical environment of palladium in solution can be either the same as in the solid state or different. Whereas in CD2Cl2 the co-ordination sphere remains intact, partial dissociation of the nitrogen ligand occurs in co-ordinating solvents. The complexes were found to be very active catalyst precursors in the CO–olefin co- and ter-polymerisation reactions. Detailed investigation of their catalytic activity allowed the catalyst precursor to be considered as the result of the assembly of different parts, each with a well defined role. In particular, the dissociated N-donor modulates the proton concentration, thus affecting the length of the polymeric chain.

The hydrocarboalkoxylation of propene promoted by a [PdCl 2 (PPh 3 ) 2 ]−PPh 3 catalyst precursor occurs (at 100 – 110 °C, P CO 10 – 100 atm) with high selectivity towards the branched isomer when a solvent is added to the alkanol. The selectivity increases on increasing the solvent/alkanol ratio, or on increasing P CO , or in the presence of LiCl, and decreases upon increasing the concentration of PPh 3 . The results are discussed in terms of steric effects. The yield decreases on increasing the solvent/alkanol ratio, or on increasing the concentration of PPh 3 , or upon decreasing P CO . Primary or secondary alkanols show comparable reactivity; tertiary alkanols give poor yields. The yield can be improved in the presence of molecular hydrogen without affecting the regioselectivity.

Two new bis(diphenylphosphino) amines, N,N-bis(diphenylphosphino) benzidine 1 and N, N-bis(diphenylphosphino)- 3,3-dimethoxybenzidine 2 were prepared by aminolysis. Their corresponding oxides, sulfides and selenides were readily prepared by reaction with hydrogen peroxide, elemental sulfur or grey selenium, respectively. Symmetric dinuclear palladium and platinum complexes were also isolated from the reaction with [M(cod)Cl-2] (M = Pd or Pt, cod = cycloocta-1,5-diene). All compounds were characterized by IR and NMR spectroscopy and elemental analysis and the structure of [(Ph2P)(2)N-C6H4-C6H4-N(PPh2)(2)] was determined by single crystal X-ray diffraction. The catalytic activity of palladium complexes in Suzuki coupling reactions was also investigated. (C) 2012 Elsevier B.V. All rights reserved.

The first diiodo palladium complex with nucleophilic benzothiazole carbenes as ligands has been synthesized and characterized. The complex, which is extraordinarily stable towards heat, oxygen, and moisture, has been found to show good catalytic activity in the Heck coupling reaction.